I might get some blowback for this but I tried the prime rib at The Greenhouse in August. It was ok, pretty basic, not a lot of flavor. The johnny cake was excellent. I doubt I would order the prime rib again. I have never had lobster there so I cannot comment on that.
Personally, I would go with Jax and their filet and lobster tail. While I really enjoy their beef short rib, I have had excellent filets there several times. You could actually try both places and give us a comparison.
Many restaurants near where I live have taken prime rib off the menu due to inconsistency in quality. Prime rib can be either really good, just ok or less than desirable. It depends on the quality (most would not be "prime" but "choice" or lesser grade) and preparation has a lot to do with it.
Good luck.
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